🐎 don't return a Promise when it's not time to yield

thanks @bastawhiz — https://news.ycombinator.com/reply?id=38880223&goto=item%3Fid%3D38864791%2338880223

src/yieldOrContinue.ts

@@ -18,10 +18,8 @@ import SchedulingPriority from './SchedulingPriority'
 // eslint-disable-next-line @typescript-eslint/promise-function-async
 export default function yieldOrContinue(
     priority: SchedulingPriority = 'user-visible',
-): Promise<void> {
+): Promise<void> | void {
     if (isTimeToYield(priority)) {
         return yieldControl(priority)
     }
-
-    return Promise.resolve()
 }